Fast dynamic response CRM boost PFC converter based on controllable current source

Abstract

The invention discloses a fast dynamic response CRM (critical conduction mode) boost PFC (Power Factor Correction) converter based on a controllable current source, which comprises a main power circuit and a control circuit, wherein the control circuit comprises a controllable linear current source circuit, a divider, an output current sampling circuit, an output voltage error amplifier, a drivingcircuit, an RS trigger, a comparator and a sawtooth wave voltage signal generating circuit. The voltage-type CRM boost PFC converter generates an error amplification signal vea through an output voltage error amplifier, and the error amplification signal vea is intersected with sawtooth waves to generate a turn-off signal of a switching tube, so as to control the conduction time of the converter.According to the invention, the controllable linear current source circuit is utilized, when the load change is detected, the magnitude of the output current Idc of the controllable linear current source circuit is changed, and the conduction time of the switching tube is changed under the condition that vea is hardly changed, so that the converter quickly enters a new steady state. The dynamic response speed of the voltage type CRM boost PFC converter is increased, and the overshoot theory is zero.

Description

technical field [0001] The invention relates to the technical field of an AC-DC converter of a power conversion device, in particular to a fast dynamic response CRM step-up PFC converter based on a controllable current source. Background technique [0002] In order to improve the dynamic response of the PFC converter. At present, the academic community has proposed the following methods: The first one is load current feedforward and input voltage feedforward, which are used to provide fast compensation to the load and input voltage respectively, so as to effectively reduce the dynamic overshoot of the output voltage. However, the selection of the optimal feed-forward gain that can provide accurate compensation requires accurate modeling of the PFC converter; the second is sliding film control, but the adjustment time under sliding mode control still depends on the configuration of the output voltage loop parameters, and does not shortened, and this method may cause distorti...

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